Ruthenium sulfur containing

In recent years, the asymmetric hydrogenation of prochiral olefins have been developed in the presence of various chiral sulfur-containing ligands combined with rhodium, iridium or more rarely ruthenium catalysts. The best results have been obtained by using S/P ligands, with enantioselectivities of up to 99% ee in... 

On the other hand, one of the first chiral sulfur-containing ligands employed in the asymmetric transfer hydrogenation of ketones was introduced by Noyori el al Thus, the use of A-tosyl-l,2-diphenylethylenediamine (TsDPEN) in combination with ruthenium for the reduction of various aromatic ketones in the presence of i-PrOH as the hydrogen donor, allowed the corresponding alcohols to be obtained in both excellent yields and enantioselectivities, as... 

L.G. Shaidarova, S.A. Ziganshina, L.N. Tikhonova, and G.K. Budnikov, Electrocatalytic oxidation and flow-injection determination of sulfur-containing amino acids at graphite electrodes modified with a ruthenium hexacyanoferrate film. J. Anal. Chem. 58, 1144-1150 (2003). 

In contrast to sulfur (Section 45.7), relatively little has been published on ruthenium complexes containing selenium and tellurium ligands. 

Transition metal surfaces enriched with S, Se and Te, have been considered as candidates for DAFC cathode catalysts [112-115], For example, ruthenium selenium (RuSe) is a weU-studied electro-catalyst for the ORR [116, 117]. The ORR catalysis on pure Ru surfaces depends on the formation of a Ru oxide-like phase [118]. Ru is also an active catalyst for methanol oxidation. On the other hand, the activity of the ORR on RuSe is found not be affected by methanol [116]. RuS, has also been reported insensitive to methanol [119-122], DPT studies of model transition metal surfaces have provided with atomistic insights into different classes of reactions relevant to fuel cells operation, such as the hydrogen evolution [123], the oxygen reduction [124], and the methanol oxidation [125] reaction. Tritsaris, et al. [126] recently used DPT calculatimis to study the ORR and methanol activation on selenium and sulfur-containing transition metal surfaces of Ru, Rh, Ir, Pd, Co and W (Fig. 8.9). With RuSe as a starting point, the authors studied the effect of the Se on... 

The sulfur-containing receptors have little affinity for hard cations but can form extractable host-guest complexes with soft cations such as Ag+, Hg +, T1+, Pd +, and Pt +. Silver is found to interact strongly with sulfur [138, 139]. It was even possible to isolate 1 1 host-guest silver and mercury complexes in a large sulfur-containing macrocycle a linear HgC molecule is hosted in the cavity, but in the 1 2 complex a second mercury atom is externally attached to the ruthenium atom [140-142]. Palladium and platinum are also selectively complexed by polythia-coronands [143-148]. Some X-ray diffraction studies on palladium [147, 148] and platinum [143, 145] complexes established that the coordination of the metal occurs by interaction with the sulfur sites. 

The metal ruthenium possesses several favorable chemical properties and it may be a strong candidate to form a basis for rational anticancer drug design [104,105]. For instance, several ruthenium(II) and ruthenium(III) complexes (Scheme 5.5) exhibit a high antitumor activity both in vitro and in vivo [2,106,107]. Therefore, the reactions of Ru and Ru complexes with DNA and sulfur-containing amino acids as well as proteins has been studied by NMR and other spectroscopic methods (e.g. HPLC). Such studies may facilitate the development of an additional structure-activity relationship and allow more selective, potent and less toxic anticancer drugs to be designed. 

Ruthenium was electrochemically deposited on a platinvim foil by the same method. The electrode was rinsed and transferred to the cell containing 3 M sulfuric add with 1 M methanol. Cyclic voitammograms were taken on the as-is electrode and after various ruthenium stripping at anodic potentials as shown in Figs. 4-8. The features of the voitammograms are stimmarized as follows ... 

Concerning the M=Co, bond, most of the reported examples result from inter- or intramolecular additions of anionic nucleophiles containing at least two reactive heteroatoms. Thus, sodium dimethyldithiocarbamate was found to react with the cationic allenylidene [RuTp(=C=C=CPh2)(PPh3)2] [PFg] (76) to generate the alle-nyl-metallacycle 77 (Scheme 26) as the result of the nucleophilic addition of one of the sulfur atoms at the Cq, carbon and subsequent coordination of the second sulfur to the ruthenium center, with concomitant release of a triphenylphosphine ligand [282]. Complex 77 could also be synthesized by treatment of the neutral derivative... 

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